Evaluate a mathematical expression.
math(EXPR <variable> "<expression>" [OUTPUT_FORMAT <format>])
Evaluates a mathematical <expression> and sets <variable> to the resulting value. The result of the expression must be representable as a 64-bit signed integer.
The mathematical expression must be given as a string (i.e. enclosed in double quotation marks). An example is "5 * (10 + 13)". Supported operators are +, -, *, /, %, |, &, ^, ~, <<, >>, and (...); they have the same meaning as in C code.
Hexadecimal numbers are recognized when prefixed with 0x, as in C code.
The result is formatted according to the option OUTPUT_FORMAT, where <format> is one of
For example
math(EXPR value "100 * 0xA" OUTPUT_FORMAT DECIMAL) # value is set to "1000"
math(EXPR value "100 * 0xA" OUTPUT_FORMAT HEXADECIMAL) # value is set to "0x3e8"